Apparatus for making corrugated tubing



Aug. 21, 1945. D. INGALLS APPARATUS FOR MAKING CORRUGATED TUBING FiledOct. 31, 1942 2 Sheets-Sheet l I N VEN TOR.

ATTORNEY Aug. 1945. D. INGALLS 2,383,253

APPARATUS FOR MAKING CORRUGATED TUBING Filed Oct, 51, 1942 2Sheets-Sheet 2 I r. 1 I? J I toc Patented Aug. 21, 1945 APPARATUS FORMAKING CORRUGATED TUBING David Ingalls, Westfield, N. J assignor toTlteflex, Inc., a corporation of New Jersey Application October 31,1942, Serial No. 464,004

11 Claims.

stance the tube as shown and described in the patent to L. H. BrinkmanNo. 1,198,392 patented September 12, 1916, which tube may be made by theapparatus as shown and described in the patent to W. H. Fulton et al.No. 1,492,075 patented April 29, 1924, and also the patent to R. H.Stone No. 1,905,762 patented April 25, 1933, the flexibility and otherdesirable properties of the tube are increased by compressing the tubeas it comes from the die and thereby reflexing the corrugation sideswith relation to the axis of the tube. This has been accomplished, asset forth in the said Patent No. 1,198,392 by passing a rod through thetube, there being nuts on the rod at the ends of the tube which, whenscrewed up, compress the tube and reflex the corrugation sides. It isalso proposed in the said Patent No. 1,198,392 that the tube might becompressed in a hydraulic press. Such operations, however, require thatthe tube operated upon shall be in comparatively short lengths so thatthe operation of forming the compressed tube shall be intermittent ascontrasted with continuously forming such tube for as long a time as maybe desired, and also the operation was laborious and required great careto prevent inaccuracies in the product.

It is an object of the present invention to provide a means forcontinuously operating upon a helically corrugated tube to compress thesame and to reflex its corrugation sides.

It is a further object of the invention to provide an improved means forcompressing the helically corrugated tube and reflexing the sides of itscorrugations by providing means for operating upon the tube comprisingmeans for forcin the tube longitudinally, continuously and indefinitely,and retarding the longitudinal movement of the tube whereby it iscompressed and the corrugation sides reflexed with relation to the tubeaxis. Although this may be accomplished by various other apparatus, oneembodiment for effecting this object may comprise two abutments betweenwhich the tube is compressed, there being at one abutment means fordefining a helical path of a given pitch and at the other abutment meansfor defining a helical path of less pitch for the helical corrugation,with means for rotating the tube whereby it is caused to pass throughthe said paths and the tube is compressed between the abutments and thecorrugation sides reflexed. In this embodiment, the abutment path ofgreater pitch in conjunction with the tube rotating means, constitutesthe means for forcing the tube longitudinally and the abutment path ofless pitch constitutes the means for retarding the longitudinal movementof the tube. This construction also permits the continuous formation ofthe compressed tube.

It having been found that the compression of the tube between theabutments as specified is facilitated by initially compressing the tubeto the desired condition, it is a further object of the invention toprovide means to operate in conjunction with the said abutments forinitially compressing the tube.

It is a further object of the invention to provide for the initialcompression of the tube as referred to by making the abutmentsrelatively movable.

A further object of the invention is to provide for the proper relativelocations of the abutments when in continuous tube-compressing relationto the other abutment.

A further object of the invention is to provide means for properlyrelatively locating the abutments in position for initially compressingthe tube as referred to.

In the passage of the tube through the abutments having paths ofdifferent pitch as referred to, it is found that the tube has a tendencyto squirm or turn about the axis independently of the means for rotatingthe tube as a whole, and it is an object of the invention to providemeans for permitting this squirming of the tube so as to permit the tubeto properly adjust itself to the apparatus. This may be accomplished bymaking the tube corrugation engaging members at one of the abutmentsrotary so that the tube is permitted to "squirm into position and is notheld in a distorted condition.

It is a further object of the invention to provide means whereby the dieforming the corrugated tube from the strip acts as one of the two compressing abutments and themandrel operating in conjunction with the dieforming the tube acts as means for rotating the tube in the compressingoperation. This greatly simplifies the apparatus, making the formationand compression of the tube a continuous operation, the apparatus beingpractically unitary and the tube as delivered by the apparatus being inits compressed condition. Among other advantages it may be noted thatthe tube being in compressed condition as it leaves the apparatus, muchspace is economized over the situation where it is necessary to makeprovision for the length of tube as delivered by the die in itsuncompressed condition. This is of great importance under congestedfactory conditions.

It will appear that means herein disclosed may be used to compress orchange the pitch of other helical members than a tube corrugation andfurther objects of the invention are to provide improved means apphcableto the compression or changing the pitch of helical members other thantube corrugations.

Other an ancillary objects of the invention will appear hereinafter.

- In the accompanying drawings which illustrate the invention Fig. 1 isa side elevation of apparatus embodying the invention, the movableabutment being shown in continuous compressing position;

Fig. 2 is a top plan view of the apparatus of Fig. 1; I

Fig. 3 is an end elevation of the apparatus of Fig. 1 looking from theleft of the latter figure;

Fig. 4 is a section, with certain of the parts omitted for the sake ofclearness, on the line 4-6 of F18. 1;

Fig. 5 is an enlarged view, partly broken away and partly in section,showing the relative positions of the abutments to each other and to thetube and also the condition of the tube with the parts in position forthe initial compression;

Fig; 6 is a view similar to Fig. 5 but showing the relative positions ofthe abutments and tube and the condition of the tube after initialcompression 1find during the continuous compressing opera- Fig. 'l is aside elevation of the apparatus of Fig. 1 an to the same scale, certainof the parts being omitted and to the movable abutment being in extendedposition for the beginning of the initial compression of thetube;

Fig. 8 is a horizontal section with certain of the parts omitted andothers broken away, showing a modified structure of the movable abutmentin continuously compressing position; and

Fig. 9 is a section on a reduced scale of a portion of the movableabutment of Fig. 8 showing relative positions of the rotary members ofthe abutment with relation to the tube when in noncompressing position,but in position for initiating the initial compression.

Referring to the drawings, and first to Figs. 1 to 7 inclusive, theapparatus comprises a die with a centrally rotating mandrel 2 forforming a flexibie, metal, helically corrugated tube from a strip, whichmay be substantially as shown in the patcut to R. H. Stone No. l,905,762issued April 25, 1933;

To one end of the die is secured a supporting cap 3 by means of theclamping screws 4' for the parts of the die, which are screwed into thecap. The cap has a central hole 4 through which the tube 5 discharagedby the die may pass.

Rotatablymounted upon the cap 3 is a shaft 5 having a central operatinghandle 1. Fixed to the ends of the shaft t are arms 8 and 9 havingforked ends 80 and ii. The forks it and ii embrace the pins or gudgeonsl2 and i3 fixed in the side of a frame it sliding on the guide rods l5and I6 fixed in the capfl, The frame it has a central opening ii for thepassage of the corrugated tube and rotatably mounted in the frame M arethe rollers i8 and I9, which'are upon diametrically-opposite sides ofthe tube. These rollers have flanges 20 and 2| adapted to extend inbetween the corrugations of the tube and longitudinally displaced fromeach other so as to define a helical path for the outer portions of thecorrugation which is of the pitch of the tube corrugation whencompressed the desired amount.

In the apparatus of Figs. 1 to '7 the corrugation engaging portions ofthe flanges are on diametri cally opposite sides of the tube so thatsuch errgaging portions are displaced longitudinally along the tube by adistance equal to one-half the corrugation pitch when the tube is incompressed condition. The flanges 25 and M are also set at anglescorresponding to the corrugation pitch of the compressed tube.

To hold the frame it and its carried rollers at the proper distance fromthe die to effect the desired compression, during operation afterinitial compression, a latch 22 is pivoted on the cap 3 and has a slot28 adapted to receive the pin It on the frame it when the last is incompressing position and to hold such frame in that position against thepressure upon it of the advancing corrugated tube.

The frame M and its carried parts may be slid outwardly upon the rods i5and It away from the die to a predetermined position prior to initiatingthe compressing operation, by raising the handle I when the turning ofthe shaft 8 will swing the arms 8 and a so as to move the frame itoutwardly to a position as shown in Fig. 7, such position being definedby the latch 22 by having .the shoulder 24 come against the.-

the position of Fig. l by moving the handle 7 downwardly and therebyswinging the arms 8 and 8 toward the die and moving the frame Ii intoposition for the pin it to be engaged in the slot 23.

In the use of the apparatus, the frame It will be located at thepredetermined initial distance from the die by means of the shoulder 24of the latch 22, as shown in Fig. 7. The tube 5 turning with the mandrel2 will be forced to the left (Fig. 5) by the engagement of the helicalcorrugation on the tube with the helical channels in the die, and theouter end of the tube will be threaded between the roller flanges 20 and2| so that the flanges will extend into the spaces between adjacentconvolutions of the corrugation as shown in Fig. 5, the condition of thetube'and the relative position of the parts being then as shown in Fig.5. The latch 22 being then lifted to free the pin is, the tube will beinitially compressed by lowering the handle I thereby forcing the rollerflanges 20 and 2! against the tube corrugation and toward the diewhereby the corrugation convolutions will be forced toward each otherbetween the abutment formed by the die and the other abutment comprisingthe frame it and roller flanges 20 and H. The forcing of theconvolutions of the helical corrugation toward each other will close, toa. greater or less extent, the spaces between the outer portions ofposition for instance as shown in Fig. 6 where the corrugationconvolutions come in substantial contact with each other. Thiscompression between the abutment comprising the rollers 20 and 38 on theone hand and the abutment pro-'- aseaaos 'vided by the exit end of thedie onthe other hand, not only forces together the outer portions of thetube corrugation convolutions as specified, but also acts to reflex thesides of the corrugations, as shown at 25, with relation to the axis ofthe tube, the sides oi the corrugation as delivered by the die beingsubstantially radial as shown at 2B.

Also the pressing of the corrugation convolutions toward each other asdescribed eflects a compression or shortening of the tube, and it willbe observed that the corrugation helix against which bear the rollerflanges 20 and 2| will become of a less pitch than was the case with thetube as delivered by the die (see Fig. 5). The flanges and 2| of thediametrically opposite rollers are, as above set forth, solongitudinally displaced and set at such angles as to correspond withthe helical pitch of the corrugation in the condition of the apparatusand tube as shown in Fig; 6, so that the path of the helical corrugationpast the flanges 20 and 2| is defined by such flanges as a helical pathof less pitch than that of the helical corrugation as delivered by thedie (see particularly Fig. 5).

It will be observed that in the original position (before the initialtube compression) of the movable abutment including the roller flanges20 and 2| as shown in Fig. 5, there will be a certain number ofconvolutions of the tube corrugation, with spaces between succeedingconvolutions, between the abutments. When the movable abutment has beenmoved to initially compress the tube, as for instance into the positionas shown in Fig. 6, there will be the same number of corrugationconvolutions between the abutments as in the position of Fig. 5, but thetube will be shortened by a longitudinal distance equal to the distancemoved by the movable abutment in this preliminary or initialcompression, as from the position of that abutment as shown in Fig. 5 tothat as shown in Fig. 6. This movement of the movable abutment causesthe shortening of the tube by closing up the spaces between thecorrugation convolutions to a greater or less degree, the degree ofclosing depending upon the distance moved by the abutment, the sum ofthe amounts of closing of all of the spaces between the convolutionsbeing equal to the distance moved by the abutment. The tube beinguniform in dimensions, quality of material and in other respects, thesum of the closures of all of the spaces between the abutments will beapproximately equally divided between the spaces and thus the degree ofclosure of each of the spaces will depend upon the distance moved by themovable abutment and the number of spaces between the abutments, thedegree of closure of the space between any two adjacent convolutionsbeing equal to the distance moved by the movable abutment divided by thenumber of interconvolution spaces of the corrugation between abutments.In the case illustrated the interconvolution spaces between theabutments are substantially closed up so that adjacent convolutionssubstantially touch each other. In such case the distance moved by themovable abutment would be substantially equal to the sum of theinter-convolution spaces between the abutments and there would obviouslybe no chance of inequality of closing of the inter-convolution spaces onaccount of lack of uniformit in the tube. With the parts in the positionas shown in Fig. 6, the tube, turning with the mandrel,

will be forced to the left (Figs. 5 and 6) from the die at a rateproportional to the pitch of the helical channels 21 in the die, throughwhich the tube corrugation passes. As has been stated, however, thepitch of the corrugation at the flanges 2|! and 2| is less than that ofthe corrugation at the exit of the die whereby the tube will not movethrough the roller flanges 20 and 2| at as great a speed as it isdelivered by the die but will have its longitudinal movement retarded.In one revolution, the tube at the die will move axially a distanceequal to the corrugation pitch at that point while at the flanges 20 and2| it will axially move in one tube revolution a less axial distancewhich is equal to the corrugation pitch at that point.

From the foregoing it will be seen. that the helically corrugated tubeformed from a strip by the die will issue therefrom at a certain pitchand will be engaged by the roller flanges 20 and 2| of the movableabutment which is in extended position, that is at its position inreadiness for initially compressing the tube as delivered by the die,this condition and relation of the parts being as shown in Fig. 5. Thehandle I may then be depressed to move the movable abutment toward thedie by a predetermined distance which will give the desired compressionby closing the intercorrugation convolution spaces to the desired extentas shown in Fig. 6, the corrugation sides being correspondingly reflexedwith relation to the tube axis. The rotating tube issuing from the diewith a corrugation pitch as shown in Fig. 5, will have its longitudinalmovement retarded at the roller flanges 20 and 2| which define a pitchof the corrugation corresponding to the compressed condition. Thislatter pitch being less than the pitch of the tube issuing "from thedie, it will be apparent that the longitudinal rate of feeding of thetube into the space between the abutments will be at a greater rate thanthe exit of said tube from the space between the abutments past theroller flanges 20 and 2|. The result is that the tube must be compressedto compensate for this difference in rate of feeding of the tube intothe space between the abutments and its exit therefrom. This compressionfor each revolution of the tube is equal to the difference in pitch ofthe corrugation at the die on the one hand and at the roller flanges 20and 2| on the other hand, and consequently each inter-corrugationconvolution space between the abutments will be closed by an amountequal to the difference in pitches at the two abutments as referred to,and this will continue while the corrugated tube is fed into the spacebetween the abutments by the rotation of the mandrel and engagement withthe helical channels in the die. The result is that the tube willcontinuously pass outside the roller flanges 20 and 2| in the desiredcompressed condition and with the corrugation sides correspondinglyreflexed. Inasmuch as the flanges 20 and 2| extend in between theconvolutions of the corrugation, the corrugation convolutions in passingthese flanges will be' separated to a slight extent, without beingsubstantially touching in the space between the abutments as referredto, and if the material of the tube and other conditions are such thatthe corrugations will not spring back into their contacting positionafter passing beyond the flanges 20 and 2|, such small spaces betweenthe corrugation convolutions will exist in the tube as delivered by theapparatus as illustrated by the tube at the left of the flanges 20 and2| in Fig. 6. If, however, the tube is of such material and construction that the corrugations will spring back together after passingthe flanges, the tube as delivered by the apparatus will have itscorrugation convolutions in substantial contact as it is between theabutments as shown in Fig. 6 at the right of the flanges and 2!.

It will now be apparent that the helically corrugated tube continuouslyformed and delivered by the die will be continuously and indefinitelycompressed so that the operation of forming the compressed, helicallycorrugated tube may be continuously carried on for any length of timedesire 4 Ref rring to Figs. 8 and 9 of the drawings, there is thereinshown a modified form of rotatable members for engaging the tubecorrugation on the movable abutment in place of the rollers l8 and Iiiwith the flanges 20 and El. Otherwise the apparatus may be of the sameconstruction as that already explained in connection with Figs.

- 1 to 7 inclusive.

connection with the foregoing figures.

In place, however, of the rotatable rollers l8 and It with flanges 20and 2i, there is rotatably mounted upon the frame it at diametricallyopposite points, drums 28 and 29, each such drum being rotatably mountedin the frame by means of a bolt as 36 and ball bearings as 35, and eachof the drums has longitudinally sliding and rotatable upon it aplurality of rings or annular plates 32. ,Upon the outer periphery ofeach of the rings 32 is a circumferential ridge 33. It will be ob servedthat the outer periphery of the tube corrugation is slightly rounded incross section so that even when the convolutions are pushed together sothat they touch there is a helical groove or between crevice adjacentconvolutions, and the ridges 33 are of such shape and size that theywill enter such groove or crevice and engage a corrugation convolutionwithout preventing the convolutions from coming together. The thicknessof each of the rings 32 is such that the distance between ridges 33 ontwo adjacent rings when they are in contact with each other as shown inFig. 8, shall be equal to the pitch of the helical tube corrugation whenthe tube is in the desired compressed condition and the ridges 33 on onedrum are longitudinally displaced with relation to the ridges on theother drum to correspond With the pitch of the tube cormgation when incompressed condition.

While the radial extent of each of the ridges 33 within the corrugationsis relatively small and its engaging surface with the corrugation in thecompressing operation is correspondingly reduced, it is to be noted thatthere are a plurality of ridges succeeding each other which engagesucceeding convolutions of the tube corrugation so that the aggregateengagement, at each of the drums, of the ridges with the tubeconvoiutions will be sumcient to successfully accomplish the compressingoperation, it being clear that the engagement of one ridge 33 on a drumis reenforced by the engagement of the other ridges on that drum withother of the corrugation convolutions.

Preliminary to the initial, compressing oi the tube, the movableabutment will be in its outermost position (farthest removed from thedie) when the tube 5 will be in uncompressed condition as delivered fromthe die I, and the annular rings 32 will be separated and distributedalong the tube as shown in Fig. 9. The frame It then being moved towardthe die in its initial compressing movement as described in connectionwith the apparatus of Figs. 1 to 7 inclusive, namely to the position asshown in Fig. 8, the tube will be compressed as shown in the figure lastmentioned and the rings on each of the drums will slide 1ongitudinallyupon the drum until they come against each other and against the flangeas 3. The tube then rotating with the mandrel will be fed from the diewith the corrugation at a greater pitch than is defined atthe rings 32o! the moving abutment wherefore the longitudinal progress of the tubewill be retarded in passing the projections whereby the tube will becompressed and the sides of the corrugation reflexed as explained inconnection with the apparatus of Figs. 1 to 7 inclusive, and thecontinued rotation of the man drel will continuously form the tube fromthe strip, force it from the die and cause the retardation at the movingabutment and consequent compression of the tube for any length of timedesired.

While the invention has been illustrated in what are considered its bestapplications it may have other embodiments without departing from itsspirit and is not therefore limited to the structures shown in thedrawings.

What I claim is:

1. In means for compressing a helically corrugated tube, the combinationwith an abutment defining a helical path of a given pitch for thehelical corrugation of said tube passing therethrough, of asecondabutment defining a helical path or the helical corrugation oi lesspitch than the aforesaid path, said second abutment being adapted toreceive the said tube from said first mentioned abutment, and means forrelatively rotating said tube and said abutments, said abutments beingrelatively longitudinally movable to initially compress the said tube.

2. In means for compressing a helically corrugated tube, the combinationwith an abutment having a helical channel at a certain pitch for thepassage of th tube corrugation, a second I abutment defining a helicalpath for the said helical corrugation, the last mentioned helical pathbeing '01 less pitch than that of said channel, means for relativelyrotating said tube and said abutments, guide bars extending from thefirst mentioned abutment and upon which said second abutment slides, andlever means :lor moving said second abutment along said guide bars.

3. In means for compressing a helicaily corrugated tube, the combinationwith a die adapted to form a helically corrugated tube from a strip andforming an abutment defining a helical path of a given pitch for thecorrugation of said tube, of a second abutment defining a helical pathfor said corrugation of less pitch than the aforesaid path, said secondabutment being adapted to receive the said tube from said die and beingin substantial alignment therewith and a rotating mandrel centrally ofsaid die androtating the said tube within said die and said secondabutment. said die and second abutment being relatively movable toinitially compress the said tube.

4. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugation forming meansprising a die to form a tube, said die having helically disposed tubecorrugation forming means of a given pitch, roller means helicallydisposed on opposite sides of th tube of diflerent pitch associated withthe die to engage the tube corrugations after formation thereof, andmeans to move said roller means longitudinally with respect to said die.

6. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugation forming meansof a given pitch, helically disposed roller means of a different pitchassociated with the die to engage the tube corrugations after formationthereof, said roller means being adapted to fit between-adjacentcorrugations of the tube, and means to move said roller meanslongitudinally with respect to said die.

7. Means for making flexible metal tubing comprising a die to form atube, said die havin helically disposed tube corrugation forming meansof a given pitch, helically disposed roller means of a diiferent pitchassociated with the die to engage a group of adjacent tube corrugationsafter formation thereof, and means to move said roller meanslongitudinally with respect to said die.

8. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugation forming meansof a given pitch, helically disposed roller means of a diiferent pitchassociated with the die to engage the tube corrugations after formationthereof, means to fix the location of said roller means at one positionlongitudinally with respect to said die, and means to move said rollermeans to a second flxed location longitudinally with respect to saiddie.

9. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugation forming meansof a given pitch, helically disposed roller means of a different pitchassociated with the die.

to engage the tube corrugations after formation thereof, means to fixthe location of said roller means at one position longitudinally withrespect to said die, and a manually operable lever to move said rollermeans to a second fixed location longitudinally with respect to said dieand to initially compress said tube.

10. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugations forming meansof a given pitch, helically disposed roller means of a different pitchassociated with. the die to engage the tube corrugations after formationthereof, adjustable means to fix the location of said roller means atone position longitudinally with respect to said die, adjustable meansto move said roller means to a second fixed location longitudinally withrespect to said die;

11. Means for making flexible metal tubing comprising a die to form atube, said die having helically disposed tube corrugation forming meansof a given pitch, helically disposed roller means of a different itchassociated with the die to engage the corrugations after formationthereof, means to fix the location of said roller means at a positioncorresponding to a pre-determined open-corrugation positionlongitudinally with respect to said die, and means to move said rollermeans to a second fixed location corresponding to closed-corrugationposition longitudinally with respect to said die.

DAVID INGALLS.

